Fatty acid esters having amphoteric properties



Patented Nov. 6, 1945 FATTY ACID ESTERS HAVING AMPHOTERIC PROPERTIES John w. Orelup, Short Hills, N. J.

No Drawing. Application June 25, 1940,

Serial No. 342,279

8 Claims. (Cl.

This invention relates to esters of alcohols with higher molecular weight organic acids, characterized by the presence of a primary amino group therein. It also relates to methods for effecting condensation between alcohols and high molecular weight acids to produce ,acid esters containing primary amino groups.

I have found that when certain alcohols possessing primary amino groups are condensed with higher molecular weight acids, esters are obtained and the compounds resulting from such condensations contain primary amino groups rendering them more basic than condensation 'prod ucts of acids with alcohols which contain no such groups, or acid amides in which the amino group is substituted.

My new compounds are synthesized from fatty acids and alcohols containing primary amino groups which are attached to secondary or tertiary carbon atoms. It is a peculiar property of such alcohols that when condensed with acids they yield esters rather than amides. The process of the present invention is carried on at a sufficiently elevated temperature to insure the removal of water in the reaction between the acid and the alcohol so that the compounds obtained are true esters rather than salts or soaps.

My new compounds have been found to have wide uses as dispersing and wetting agents. As they are cation active, manyvaluable applications have been found, based on this property. Some of the uses to which these compounds may be put are softening textiles, fiocculating acidic compounds and level dyein with basic dyes. They may further be used as self emulsifying oils and waxes and for emulsiflcation of oils, waxes and the like as well as to increase the fastness of direct dyeing. Many of the compounds may be used as syntheti waxes to replace natural waxes in polishes, creams and like compositions. The compounds also have cosmetic and many other applications.

It is a characteristic of these new compounds that they contain both hydrophilic and oleophilic groups and they are further characterized by the presence of the primary amino group which makes the compounds useful formany purposes for which other compounds are not available.

The higher molecular weight acids which may be condensed with amino alcohols to form the compounds of the present invention are preferably acids of the fatty type, the aliphatic acids being preferred. As examples of fatty acids which may be used in this connection I may mention caproic, caprylic, ,capric, lauric, myristic, palmitic, oleic, stearic, ricinoleic, linoleic, arachidic, behenic, lignoceric, palmitoleic, linolenic,

oleostearic, clupandonic acids and mixtures of these acids and others such as cocoanutfatty acids which contain substantial quantities of 260-401) lauric, myristic, palmitic and oleic acids. The acids obtained from cotton seed, corn, peanut,

sun flower and similar vegetable sources may also be used. The above list is intended to be illustrative and not; limiting as any acids of predominantly fatty character having at least six carbon atoms may advantageously be employed.

The amino alcohols which I condense with fatty acids according to this invention may be represented by the following eneral formula:

in which R1, R2 and R: may be H, alkyl or alkylcl and the sum of the carbon atoms in R1 and Rz' is at. least one. Specific examples of such compounds are 2-amino Z-methyl 1-3 propanediol and the higher substituted homologues of the same compounds such as the Z-amino Z-ethyl 1-3 propanediol and the propyl and iso-propyl .compounds, tris (hydroxymethyl) aminomethane, 2-amino Z-methyl 1-propanol and the ethyl, propyl, and iso-propyl substituted compounds, 2- amino 1 propanol, iso-propanol and butanol, 2- amino 1-3 propanediol, 3-amino 3-methyl 2- butanol; 4-amino 5-methyl 3-hexanol, S-amino '4-octanol.

The method of reacting these products comprises'a direct condensation of a suitable amount of the desired amino alcohol with a similar molecularly suitable amount of the fatty acids. The two are heated to dehydrating temperatures in a suitable flask provided with .means for removing the evolved water and the composition of the reaction mixture is gauged by the reduction of the acid number thereof. The products are variously fairly light colored oils and waxy substances of various consistencies and colors. c

A further object of my present invention is to produce new sulfated fatty acid ester amino compounds starting with certain of the compounds of the foregoing.

I have found that bythe sulfation of certain of the above condensation products e. g. the amino propanediols and triols with fatty acids particularly those. having at least six carbon atoms, new surface active compounds are produced which have the singular property of being both cation active and anion active. That is to say, that the ionizing part of the surface active molecule contains both an acidic and a basic radical. This unique characteristic allows new effects to be produced. g

It is believed that surface active compounds of an amphoteric character are new. Heretofore it has been recognized that anion active surface tension agents and cation active agents are anof the other. For example, emulsions are broken where anion active emulsifiers are brought in con-- active materials now described, this will not occur.

As examples of my new condensation products 'and process I offer the following, it bein understood that the examples are not to be considered in any way as limiting but are merely illustrative of the process employed to obtain the various products:

Example No. 1.Into a distilling flask or suitable distillation kettle is placed 210 pounds of mixed cocoanut fatty acids, and 114 pounds of Z-amino 2-methyl 1,3 propanediol. The temperature of the mixture is brought to 173 C., wateris evolved from the mixture and condensed by external cooling. The temperature is gradually raised in the course of 2 hours to 208 C. During this time the condensate amounts to 28 -pounds of water together with some oil. The acid number of the mixture is dropped from an initial point of 159.5 to 1.9 at the end of the two hour period indicating substantial completion of the reaction. The product is a light yellow oil. This product forms colloidal solutions in water, is more soluble in acid solutions which tend to form salts, is useful as a dispersing and wetting agent and is suitable for the softening of textiles. Titration of the product shows that the condensation has taken place of the fatty acid with one of the hydroxyl groups of the propanediols, thus leaving a primary amino group free. A yield of over 90% is obtained.

Example No. 2.-Into a similar reaction kettle as used in Example No. 1, 210 pounds of cocoanut fatty acids are charged and 109 pounds of 2- amino 2-methyl, l-propanol is added. The reaction mixture is brought to 175 C. and the heating continued for six hours. At this time the acid number of the mixture has dropped from 160.9 to 5.3 showing approximate completion of the reaction. The product of this reaction is a thin tan colored oil having more basic properties than Example No. 1. The product is colloidally soluble in water, especially after the addition of acids and is cation active and may the used for the emulsification of oils, waxes and also to increase the fastness of direct dyeings by after-treatments.

Example N0. 3.-l42 pounds of stearic acid (triple pressed grade) and 57 pounds of Z-amino 2-methyl 1,3 propanediol are placed in areaction kettle and heated to 185 C. The temperature is gradually raised to 215 C. in about one hour. The acid number of the mixture drops from 139.5 to 2.6. 14 pounds of distillate is obtained consisting mainly of water. The condensation is then finished and the new product is seen to be a hard practically white wax of a setting point of 36 to 37 C. The product in a 5% aqueous solution forms aostiff semi-solid emulsion and possesses excellent softening properties for textiles. It is also a good emulsifying agent and may be used as beeswax and as a synthetic wax as a substitute for natural waxes for polishes. in cosmetics, etc.

Example N0. 4.-.141 pounds of oleic acid and.

tagonistic and one tends to neutralize the action 58 pounds of 2-amino 2-methyl 1,3 propanedioi are charged into a distilling kettle and the temperature raised to 200 C. After one hour the temperature is allowed to go to 215 C. during which time 14 pounds of watery distillate is obtained and the acid number has changed from initial 143 to 1.7. The product is a light amber oil useful for imparting a soft finish to textiles. It has basic properties and in common with the other types of condensations described heretofore forms salts when acids soluble in water are dispersed therein.

Example N0. 5.- pounds of cocoanut fat y acids are mixed with 66.6 pounds of tris (hydroxy methyl) amino methane. The mixture is heated in a distilling kettle to a temperature of 190 C. taking one hour. The temperature is allowed to rise to 212 C.the distillate amounts to 14 pounds of water. The acid number has dropped from 143 to 2.3. The product is a hard nearly white wax, setting at approximately 74 C. A 5% solution of this product in water forms a semi-crystalline slurry which is adaptable for forming emulsions of oils and fats and waxes.

Example No. 6.142 pounds of triple pressed stearic acid is charged into a distilling kettle with 49 pounds of Z-amino 2-methyl l-propanol. The temperature of the mass is brought to C. and allowed to rise gradually to 235 C. taking 4 to 5 hours. At the end of this time the distillate amounts to 16 pounds of water and oil and the acid number has dropped from an initial of 149 to 5.8. The reaction is substantially finished, the product bein a soft tan colored wax, having an average setting point of 32 C. A 5% solution of this product in water is a very thick, almost solid slurry which is useful as a compound for emulsification and for the finishing of textiles.

Example No. 7.-141 pounds of oleic acidis mixed with 49 pounds of Z-amino 2-methyl 1- propanol and placed in a distilling kettle and the temperature brought to 180 C. Heat is gradually added bringing the temperature to 240 C. in

about 4-to 5 hours. The distillate amounts to approximately 25, .pounds of oil and water and the acid number has dropped from 137 to 2.6. The reaction at the end of this time is substantially finished and the product is a dark amber oil suitable for general cation active surface tension purposes and as an emulsifier and finisher.

Example N0. 8.-141 pounds of oleic acid is mixed with 66 pounds of tris (hydroxy methyl) amino methane. The mixture is charged in a .still and heated to C.; the temperature is then allowed to rise gradually to 220 C. taking 1 hours. During this time 14 pounds of distillate is collected and the acid number of the mixture drops from 135 to 4.2. The product is a hard, slightly yellowish wax of a settin point of 62 to 63 C. The product is used as a synthetic wax and as an emulsifier. A 5% solution in water forms thick curdy emulsions.

Example No- 9.142 pounds of triple pressed stearic acid ismixed with 6'7 pounds of tris (hydroxy methyl) amino methane in a suitable reaction flask. The temperature of the mass is brought to 190 C. at the end of 1 /2 hours. The

distillate collected amounts to 9 pounds and the acid number of the mixture has dropped from 136 to 1.4. The reaction is substantially finished and the product is a very hard tan colored wax of a setting point 91 to 92 C. which can be used to replace natural waxes in polishes, creams and like compositions.

used for the softening of textiles;

' heated to 195 Example No. 10.-105 pounds or cocoanut fatty acids are mixed with 49 pounds of il-aminov 1- butanol, The mixture is placedin-a'distillins kettle and temperature brought to 185 C. In the course of an hour the temperature is brought to 232 C. At the end or this time 12 pounds of distillate has been collected and the acid number has dropped frominitial of 149 to 1. The reaction is completed and the product is a light amber oil hardly soluble in water. After acidiflcation, however, it forms colloidal solutions of cation active character. The product may be Example No. 11.14l pounds of oleic acid are mixed with 49 pounds of 2-amino l-butanol. The

i .completely clear-atroom temperature.

mixture is heated in the distilling kettle 'to 186" C. and after 1 /2 hours is brought to 235 C. 12 pounds of distillate are collected and the acid number has dropped from 141 to 2. The product is a light amber oil very similar in character to the preceding Example No. 10. It may be used -for softening of textiles and the lubrication of textile fibres.

Example No. 12 -142 pounds of stearic acid are mixed with 49 pounds of'2-amino l-butanol. The mass is heated in a distilling flask to 180 and the temperature is gradually brought to 225 C. in about 2 hours. The distillate collected amounts to 14 pounds andthe acid number drops from 155 to 1.3. The product is an almost white wax of asetting point 35 to 36 C. The product is hardly dispersible in water unless acid is added to it. The product is useful as a finishing and softening agent.

Example No. 13.210 pounds-of cocoanut fatty acids is charged into a distilling vessel with 130 pounds of 2-amino 2-ethyl 1,3 propanediol. The temperature of the mass is brought to 180 C.

Example No. 17.-"-149 pounds. or ricinoleic acid and 63 pounds of 2-amino. 2-ethyl 1-3 propane-' diol are heated to 200 C. in a distilling kettle.

Over thespace or about one hourthe temperature is raised to about 230 C. at which time the acid number has dropped to about 1.5. The productis very similar to that of Example 16 though slightly less. viscous. A 5% aqueous solution acidulated with acetic acidis a clear light amber colored solution.

Example No. 18.-149 pounds of ricinoleic acid and 59 pounds of. 2-amino z-methyl l-propanol are heated in a distilling kettle to 175C. and over the space of about two hours the temperature is gradually broughtto 230 C. At theiend of that time the distillate amounts to about 10 pounds and the acid number has dropped to 2.5. The product is a heavy viscous reddish oil with a pronounced green fluorescence. A 5% aqueous solution acidulated with acetic acid is somewhat cloudy, but practically complete solubility is obtained. 1

Example No. 19.-149 pounds of ricinoleic acid and 49 pounds of 2-amino l-butanol are mixed and gradually raised, taking about 2 hours, to

220 C. The distillate amounts to 28 pounds of water and oil and the acid number of the mixture has dropped from initial of 159 to 1.5. This product is an amber fluorescent green oil dispersing in water and suitable as an emulsifier and textile assistant.

Example No. 14.-182 pounds of stearic acid are mixed with 63 pounds of 2-amino 2-ethyl 1,3 propanediol. The temperature is brought to 185 C. and then raised to 240 C. taking about 1 hours. The amount of watery distillate collected amounts to 16 pounds and the acid number has dropped from 141 to .8. The reaction is substantially completed and the product is a soft tan colored mass with a setting point of 12 C.

Example No. 15.--141 pounds of oleic acid is mixed with 63 pounds of 2-amino 2-ethyl 1,3 propanediol and the mixture is placed in adisin a distilling kettle and heated to 185 C. The temperature is broughtto 240 C. in the space of about 2 hours. The distillate at this time amounts to about 10 pounds and the acid number has dropped to 1.5. The product is a viscous oil with a green fluorescence. In a 5% solution acidulated with acetic acid the product is co]- loidally dispersed, but not clearly soluble.

Example N0. 20.-- 14'9 pounds of ricinoleic acid and 66 pounds of tris (hydroxy methyl) amino methane are heated to 195 C. in a distilling kettle and over a space of about one hour and a half the temperature is raised to 212 C. at

which time the acid number has dropped to about 3. The product is a yellow tough sticky resin with a fresh cocoanut odor. A 5% solution of this product acidulated withacetic acid shows a very slight cloudiness indicating practical complete solubility.

Example N0. 21 .256 pounds of palmitic acid and 110 pounds of 2-amino Z-methyl 1-3 propanediol are heated to 175 C. in a' distilling tilling'fiask and heated to 180 C. The temperature is gradually raised to 250 C. taking 1 hour. At the endof this time the distillate amounts to 14% pounds of water and oil and the acid number has dropped from 139 to 1.2. This product is an amber fluorescent green oil suitable for use as a softening agent and lubricant for textile fibres, also for other cation active surface tension agent uses.

Example No. 16.--298 pounds of ricinoleic acid 1 and pounds of 2-amino Z-methyl 1-3 propanediol are mixed in a distilling kettle and C. Over a space of about two hours the temperature is raised to about 220 C. At the end of this time the distillate has amounted to 21 pounds and the acid numberhas dropped to 2. The product is a viscous fluorescent oil similar in appearance to lubricating oil. A 5% flask. Over the space of about an hour and a halfthe temperature is raised to 205 C. at which time the acid number has dropped from 148.5 to 2.5. The product is ayellowish tan soft waxy paste having a solidification point of 30 to 31 C. After acidulation a 5% aqueous solution has a very slight cloudiness indicating practically complete solubility.

Example No. 2Z.-115 pounds of palmitic acid and 57 pounds of 2 -amino 2-ethyl 1-3 propanediol are mixed in: a distilling kettle and the tem perature raised to 180 C. Over the space of about 1 /2 hours the temperature is raised to 205 C. at which time the acid number has dropped to 2.5. The product is a viscous greenish fluorescent oil. Soap-like colloidally dispersed solutions of both the acetate and the hydrochloride are obtained in water, the acetate being the more soluble of the two. This product is soluble in mineral oil. The product unacidulated is substantially insoluble in water, giving a soap-like.

solution.

Example No. 23.-128 pounds of palmitic acid and 59 poundsof 2-amino 2-methyl l-propanol are placed in a distilling kettle and the temperature is raised to C. Over the space of 2 hours the temperature is gradually brought to soluble therein. A-% solution of acetate and.

hydrochloride in water indicates the superior solubility of the acetate. The solubility in mineral oil is poor.

Example 24.-128 pounds of palmitic acid and 49 pounds of 2-amino l-butanol are heated in a distillin kettle to a temperature of 195 C. and from this point gradually raised to 245 C. over the space of about an hour. At this time the acid number. has dropped to 2 and the distillate amounts to about twelve pounds. The product obtained is a soft sticky yellowish wax having a solidification point of 35 0., very slightly soluble in water and not colloidally dispersed therein. The acetate and hydrochloride form cloudy broth-like colloidal solutions in water. A 2% solution in a low viscosity mineral oil sets to a thick vaseline-like grease.

Example No. 25-128 pounds of palmitic acid and 6616 pounds of tris (hydroxy methyl) amino methane are heated in a distilling kettle to 200 C. The temperature is raised to 240 C. over a space of about one hour, at which time the acid number has dropped to 1.2 and the distillate amounts to 18 pounds. The product is a yellowish brittle wax having a solidification point of 82 to 84 C. The product is only slightly soluble in water with considerable foaming. The acetate and hydrochloride are less than 5% soluble in water at room temperature. A 2% concentration in mineral oil produces a crystalline slurry.

Example 26.-114 pounds of myristic acid are heated with 55 pounds of 2-amino 2-methyl 1-3 propanediol to 190 C. in a distilling kettle. Over the space of 1% hours the temperature is raised to 245 C., at which time the acid number has dropped to 0.2 and the distillate amounts to about 15 pounds. The product solidifies to rosette-like crystals of light tan soft wax, having a solidification point of 31 to 34 C. The product is very slightly soluble in water; but 5% solutions of the acetate or hydrochloride show complete solubility at room temperature. A 2% solution in mineral oil gives a clear product, the viscosity of the mineral oil being slightly increased.

Example No. 27.-l14 pounds of myristic acid are heated with 63 pounds of 2-amino 2-ethyl 13 propanediol in a distilling kettle to a temperature of about 200 C. The temperature is raised over a space of about two hours to 235 C.,

at which time the acid number has dropped to 1.3 and the distillate amounts to about 15 pounds.

This product is a light tan colored oil which is very slightly soluble in water, but 5% aqueous solutions of the acetate or the hydrochloride show complete solubility. A 2% solution in mineral' oil is completely clear without any, separation.

1 Example No. 28.-114 pounds of myristic acid are heated with 59 pounds of 2-amino 2-methyl 1 propanol in a distilling kettle to a temperature of 185 C. and then over a space of two and onehalf hours the temperature is gradually raised to 215 C., at which time the distillate amounts to 15 pounds and the acid number has dropped to 3. The product is a tan colored soft greaselike slurry having a solidification point of 0 to 29 C. The product is very slightly soluble in water, forming a soap-like dispersion. At room temperature the acetate and the hydrochloride are less than 5% soluble in water, but go into solution upon heating. A completely clear 2% solution may be made in mineral oil.

Example No. 29'.114 pounds 01. myristic acid and 49 pounds of 2-amlno l-butanol are heated in a distilling kettle to 190 C. The temperature is then gradually raised to 250 C. over the space or one hour, at which time the distillate has amounted to 16 pounds and the acid number dropped to 0.7. The product is a soft tan granular grease, which solidifies at approximately 27 C. The product is very slightly soluble in water, but the acetate and hydrochloride form 5% aqueous solutions with only slight cloudiness. A 2% solution in a light mineral 011 sets to a heavy transparent gel.

Example No. 30.--114 pounds of myristic acid and 66.6 pounds of trisv (hydroxy methyl) amino methane are heated in a distilling kettle to 185 C. When the temperature has reached 250 C. over the space of two hours the distillate amounts to about 15 pounds and-the acid number is 1. The product is a tan colored brittle wax having a solidification point of 82 C. While it is only slightly soluble in water, a completely clear 5% solution of the acetate or hydrochloride can be made. A 2% solution in mineral oil is cloudy with a crystalline slurry at room temperature.

Example No. 31.5 8-.3 pounds of caproic acid are heated with 55 pounds of 2-amino 2-methyl 1-3 propanediol to about185. C. in the space of an hour. The temperature reaches 240 C. at which time the distillate equals about 16 pounds and the acid number has dropped to 3. The product is a thin light amber colored oil, very slightly soluble in water and completely soluble in mineral oil. A clear 5% solution in water of the acetate may be made.

Example No. 32.58.3 pounds of caproic acid are heated with 63 pounds of 2-amino 2-ethyl :3 propanediol in a distilling kettle to about 200 C. The temperature is gradually raised to 240 C. over the space of about one and a half hours, at which time the distillate is about 1'7 pounds and the acid number has dropped to 1.3. The new product is a thin amber oil with green fluorescence which is slightly soluble in water. The acetate and hydrochloride are not completely soluble in 5% concentrations in water. A 2% solution in mineral oil of the compound may be made.

Example 'No. 33.58.3 pounds of caproic acid and 59 pounds of 2-amino 2-methyl propanol are heated in a distilling kettle to about 185 C. and

then taken to 250 C. over the space of about one hour and a quarter, at which time the acid number has dropped to below 3 and the distillate amounts to 13 pounds. The new product is a thin amber colored liquid insoluble in water and soluble in mineral oil. The acetate and hydrochloride are only sli htly soluble in water.

Example No. 34.-58.3 pounds of caproic acid are heated in a distilling kettle with 49 pounds of 2-amino l-butanol to-182 C. The temperature is then raised to 225 C. over a space of two hours, at which time the distillate amounts to 11 pounds and the acid number has dropped to 2.3. This product is a thin amber oil insoluble in water and very slightly soluble in mineral oil. The acetate and hydrochloride are slightly soluble in water.

' Example No. 35.-55 pounds of caproic acid are heated with 63 pounds 01' tris (hydroxy methyl) amino methane in a distilling kettle to about 185 C. The temperature is raised to 250 C. over the space of an hour and a quarter at which time the distillate amounts to 13 p unds and the acid number has dropped to 2.8. The product is a soft yellow wax having a solidiflcaq tion point of 31 to 37 C. The product is heavier than water and only slightly soluble therein, but the acetate and hydrochloride are completely soluble in aqueous solution. A 2% solution in mineral oil gives a crystalline slurry with undissolved material.

Example No. 36.100 pounds of lauric acid and 59 pounds of 2-amino 2-methyl 1-3 propanediol are heated in a distilling kettle to 180 0. Over a space of two hours the temperature is gradually raised to 235 C. At the'end of this time the distillateamounts to 14 pounds and the acid number has dropped from 174 to 3. The new product is an almost colorless oil,- tending to emulsify in water solution and completely soluble in mineral oil. A 5% aqueous solution of the hydrochloride and acetate are completely soluble at C.

Example No. 37.-100 pounds of lauric acid and 69 pounds of 2-amino 2-ethyl 1-3 propanediol are heated together in a distilling kettle to 180 0. Over a space of two and three quarter hours the temperature is gradually raised to 245 C. At the end of this time the distillate amounts to 14 pounds and the acid numberhas dropped from 168 to 1.7. The product is a light amber oil, partially emulsiflable in water and completely soluble in mineral oil. The acetate and hydrochloride are completely soluble in 5% aqueous solution.

Example No. 38 .100 pounds of lauric acid and 66 pounds of2-amino 2-methyl l-propanol are heated together in a distilling kettle to a temperature of 182 C. Over a space of three and three-quarter hours to 220 C. At the end of this time the distillate amounts to 17 pounds and the acid number has dropped from 1'74 to 6. The product is a light amber oil, partially emulsiflable in water. A 2% solution in mineral oil is slightly cloudy. A 5% aqueous solution of the acetate tends to separate 1 into needle-like crystals. A 5% solution of the hydrochloride is a broth-like slurry.

Example No. 39.100 pounds of lauric acid and 51 pounds of 2-amino l-butanol are heated together in a distilling kettle to a temperature of 180 0. Over a space of two hours the temperature is gradually raised to 210 C. During this time the acid number drops from 171 to 2. The product is a soft tan wax with a solidification point of 12 to 15 C. The product is partially emulsiflable in water, and a 2% solution in mineral oil sets to a thick soft gel at room temperature. A 5% concentration of acetate or hydrochloride is not completely soluble in water. The acetate is more soluble than the hydrochloride. Example No. 40.--100 pounds of lauric acid and 68 pounds of tris (hydroxy methyl) amino methane are heated together in a distilling kettle to 170 C. Over a spaceof an hour and a half the temperature is gradually brought to 210 C. At the end of this time the distillate amounts to 12 pounds and the acid number has dropped from 156 to 2. The product is an almost white hard brittle wax with a solidification point of 83 C. An aqueous solution partially emulsifles and solution in mineral oil sets foams, while a 2% hydrochloride or acetate of a to a soft gel. The

5% t:oncentration of this compound is soluble in wa r.

It will be understood that the same compoun may be obtained by condensing the equivalent nitro compounds with fatty acids and subsequently reducing the same. It will also be seen that the acid halides or esters or the fatty acids may be used, particularly the methyl, ethyl, or glycerol esters and the corresponding alcohols are splitout in the condensation reaction instead of water as described in the examples. The temperatures given in the various examples may be varied to a considerable degree without impairing the results of the reactions, it being'understood that in general the lower the temperature, the slower the reaction and also that in any event temperatures must be kept high enough to insure the removal of water or alcohol.

While for the most part condensations occur readily, catalysts may be used such as acids, acid salts,'for example sodium bisulfate, or powiilired metals, for example tin, copper or the Compounds of the present invention are distinguishable from condensation products obtained by condensing amino alcohols in which the amino group is attached to a primary carbon atom, with fatty acids,.as the compounds obtained in such reactions, as for example condensations with monoethanolamine' or mono isopropanolamine, are acid amides whereas the 'compounds obtained in the present invention the temperature is raised wherein the primary amino group is attached to a secondary or tertiary carbon atom are esters.

' The present compounds are of course distinguishable from soaps or salts obtained by reacting alcohols with acids at room temperatures or at temperatures precluding the removal of water from the scene of the reaction. Such soaps or salts have entirely diflerent. properties as they may be split into their original components as easilyas they are formed and do not lend themselves to the conditions under which the compounds of this invention may be used. By treatment of certain of the foregoing condensation products with concentrated sulfuric acid under mild sulfation conditions new sulfonic esters are bond or unreacted hydroxyl rather than at the amino group. These sulfated fatty acid esters so produced are unique in that they have both a sulfonic ester and a primary amino group.

This chemical structure lends itself to many new applications as a textile assistant and as a surface tension compound. I

The process of obtaining my new sulfated compounds comprises the sulfation of any of the foregoing compounds which comprise a fatty acid ester containing a primary amino group and a free hydroxyl group or a double bond. This ester may preferably be treated with concentrated sulfuric acid under mild sulfation conditions yielding a sulfated ester containing neighboring primary amino groups, but other methods of sulfation are of course applicable.

My new sulfated compounds have wide applications as surface active materials, their use being particularly based on their combined cation and anion activity; thus they are especially useful for their high washing value, forproducing good handling and softening-of wool and worsted, as well as for efficiency in wetting. They are further useful in softening textiles, and have a broad basis of application in the dye industry,

for example for level dyeing with basic dyes and increasing the fastness of direct dyeing. The

compounds also have broad applications in the field of emulsiflcation; for example, they may be used in insecticide emulsions, paints, and cosmetics. Other applications of these compounds will occur to those familiar with the art.

Any suitable sulfating agent may be used. I have found it particularly convenient touse 100% sulfuric acid. Variations of this procedure may be had by adding boric acid to the sulfonation mass which will result in a yield of boro sulfates, or acetic acid which will result in sulfo acetates. The following examples illustrate the sulfonation of the herein described hydroxy esters to yield amphoteric surface active agents:

Example 41 .--100 pounds of the condensation product of cocoanut fatty acid with 2-amino 2- methyl 1,3 propanediol is added gradually to a sulfonation kettle containing 100 pounds of p 100% sulfuric acid. The kettle is provided with efl'icient and sturdy arms capable of mixing a thick paste thoroughly. The temperature is kept below 40 C. or at about an average of 35 C. After all of the condensation product is added a test for completion of sulfonation is made by adding a small portion of the sulfonation mass to water. If the solution remains clear when made alkaline with sodium hydroxide, sulfonation is complete. The reaction mass at completion is a thick paste to which should be added without delay 75 pounds of ice. While continuing cooling, a 50% solution of sodium hydroxide is added until the pH of the mass is approximately 7 to 8. About 50 lbs. of the 50% sodium hydroxide is required. The product is a tan to white colored paste, soluble in water and is suitable for use directly as a textile assistant or in many other applications requiring surface tension active compounds. The product maybe dried in a spray drier or a vacuum drum drier and may be, if desired, mixed with diluents and additives.

Example 42.100 lbs. of the condensation product of tris (hydroxy methyl) amino methane and stearic acid is added gradually to 120 lbs. of 100% sulfuric acid. Again with vigorous stirring the reaction is allowed to proceed at approximate 35 C. After an hour the temperature of the mass is raised to 50 C. and stirring is continued until a test is soluble in dilute sodium hydroxide solution. The bufi colored mass is then mixed with 80 lbs. of ice and 50% of sodium hydroxide is added until the mixture is neutral to phenolphthalein. The product is a nearly white paste which may be dried in a drum drier to produce a. white powder.

Example 43.87.5 lbs. of the condensation product of 2-amino 2-methy1 1,3 propanediol and cocoanut fatty acid is added gradually with good stirring to 87.5 lbs. of sulfuric, acid at 35 0., external coolingbeing applied. The temperature is maintained while the reaction continues, the end of the reaction being shown on completion of addition by testing with a sample for clear solubility with dilute sodium hydroxide. 0n completion 350 lbs. of cold water is added. The mixture is allowed to stand over night and then filtered to remove the excess acid used in sulfonation. The pasty product is neutralized with 50% sodium hydroxide, care being taken to maintain the temperature below 40 C. The product is a slightly more yellowish and thinner paste than that described in Example 1. The final product is more concentrated than that'in Example 1 as it contains less sodium sulfate.

Eaample 44.50 lbs. of the condensation product of 2-amino 2-ethyl 1,3 propanediol and oleic acid is added gradually with good stirring to 50 lbs of sulfuric acid. By means of external cooling the temperature is maintained below 35 C. When clear solubility in dilute sodium hydroxide is shown by test 37.5 lbs. of ice are added and the solution is neutralized to phenolphthalein with the required amount of sodium hydroxide or approximately 73 lbs. The product is a soft yellowish paste.

Slightly variable results can be obtained by adding boric acid to the sulfonation mass securing boro-sulfonates, also acetic acid may be added to the sulfonation mass furnishing sulfoacetic compounds. Similar variations can be made without deviating from the invention.

This application is a continuation-in-part of copending application, Serial No. 330,062, filed April 1'7, 1940.

I claim:

1. A fatty acid mono ester of a, fatty acid containing at least six carbon atoms with an aliphatic amino alcohol, said ester containing a primary amino group in which the carbon atom binding the amino group is bound to at least two other carbon atoms, and said amino group is'unsubstituted.

2. A fatty acid mono ester of a fatty old containing at least six carbon atoms with an aliphatic amino alcohol, said ester containing a primary amino group secured to a tertiary carbon atom, said amino group being unsubstituted.

3. The process of preparing a mono ester of a fatty acid containing at least six carbon atoms, said ester containing an unsubstituted primary amino group which includes the steps of reacting a fatty acid with an aliphatic amino alcohol in which the amino group is bound by a carbon atom having at least two carbon atoms bound to it, at dehydrating temperatures, and removing the water evolved.

4. The process of preparing a mono ester of a fatty acid containing at least six carbon atoms which ester contains an unsubstituted primary amino group, which includes the steps of condensing an aliphatic amino alcohol having an amino group bound by a carbon atom which is bound to at least two other carbon atoms, with a fatty acid and removing approximately one molecular proportion of watery distillate there- .from.

5. The process of preparing a mono ester of a fatty acid containing at least six carbon atoms which ester contains an unsubstituted primary amino group, which includes the steps of condensing an aliphatic amino alcohol having at least two hydroxyl groups and an amino group bound by a carbon atom which i bound to at least two other carbon atoms, with a fatty acid, removing approximately one molecular proportion of watery distillate therefrom, and sulfatin the same.

6. Compounds within the scope of claim 1 which have a free hydroxyl group remaining after condensation, the same being sulfated by reaction of a sulfating agent with such hydroxyl group.

. '7. Compounds within the scope of claim 1 in which the fatty acid radical .is unsaturated, said compounds being sulfated.

8. The mono cocoanut fatty acid ester of 2 amino, 2 methyl, 1-3 propanediol.

JOHN W. ORELUP. 

